Fetal heart rate patterns and neurodevelopmental outcome in very low birth weight infants

Background. To evaluate the validity of fetal heart rate monitoring during the last hour prior to birth, as a predictor of long term neurodevelopmental outcome of very low birth weight infants. Methods. A total of 111 very low birth weight infants were included in the study. Fetal heart rate tracings were obtained during the last hour prior to delivery. A perinatologist, blinded to the neonatal outcome, evaluated the tracings and divided them into three groups: reassuring, nonreassuring, and pathological. Neurodevelopmental status was evaluated at age 2 years. The relationship between fetal heart rate monitoring results and the neurodevelopmental outcome at 2 years of age was assessed with a chi-square test and the Student's t-test. Results. At 2 years of age 97 (87.4%) of the children had normal neurodevelopmental function, while 14 (12.6%) had variable degrees of neurodevelopmental impairment. The fetal heart rate monitoring results were classified as reassuring (normal) in 35 cases (31.5%), nonreassuring in 56 cases (50.5%), and pathological in 20 cases (18.0%). Both normal and pathological fetal heart rate patterns were associated with similar incidence of abnormal neurodevelopmental outcome, 14.3% and 15.0% of cases, respectively (p =0.778). Pathological fetal heart rate patterns as a predictor of neurodevelopmental outcome had a sensitivity of 27%, specificity of 74%, positive predictive value of 15%, and negative predictive value of 86%. Conclusion. Electronic fetal heart rate monitoring prior to delivery is not a reliable tool for the prediction of neurodevelopmental impairment in premature infants of very low birth weight, at 2 years of age.